Providers of telecommunications services, such as AT&T, typically transport inter-city traffic in a digitally multiplexed format. Some providers of telecommunications services implement TI digital carrier systems that multiplex twenty-four constituent 64-kilobit (DS0) digitized circuits (signals) to yield a 1.544 Megabit per second (Mbps) stream. Other carriers, such as AT&T, operate transmission T3 systems that have the capacity to multiplex twenty-eight constituent Ti circuits. The constituent Ti circuits that yield the multiplexed T3 circuit are typically, although not necessarily, associated with different service offerings. For example, a typical T3 circuit may comprise individual Ti circuits associated with ADL, Intertoll, and dedicated services, to name a few.
Presently, the nature of the particular traffic carried by the constituent TI circuits of a multiplexed T3 circuit plays a role in establishing the restoration priority of that T3 circuit in the event of a failure. For example, some restoration techniques afford higher priority to T3 circuits whose constituent T1 circuits carry certain traffic, say private line traffic, than those T3 circuits that carry other types of traffic.
Aside from the nature of the particular traffic on the constituent T1 circuits of a multiplexed T3 circuit, the individual status of each constituent T1 circuit has previously played no role in the decision regarding a restoration of a multiplexed T3 circuit. Thus, assuming a set of individual T1 circuits that carry traffic of the same priority, current restoration techniques may undertake restoration of a T3 circuit having very few if any failed T1 circuits prior to undertaking restoration of a T3 circuit having many failed TI circuits. Since no account is typically taken of the actual status of the constituent circuits in a multiplexed circuit, a technician using any of several present day restoration techniques may attempt restoration of a T3 circuit containing a small number of TI circuits when in fact the T3 only contains that many active TI circuits and does not in fact require restoration.
Thus, there is need for a technique for accomplishing restoration that overcomes the deficiencies of the prior art.